Zombie Horde

Paragon Traits

Paragon Fortitude. The creature has three pools of hit points, each containing 40 hit points. All damage and healing must be completely applied to only one pool of hit points. One pool of hit points must be completely reduced to zero hit points before any damage is applied to another pool. When a pool of hit points is reduced to zero, all ongoing conditions and effects affecting the creature end immediately. After a pool of hit points has been reduced to zero, it cannot receive any healing until after a long rest. If all pools of hit points have been reduced to zero hit points, the creature is killed.

Paragon Transformation. The creature has multiple forms, each corresponding to one of the creature’s hit point pools. The creature begins the battle in one form. When that form’s hit point pool has been reduced to zero, it assumes its next form immediately. Statistics, traits, or actions keyed to a specific form are only used when the creature is in that form.

Divine Disruption. If a Cleric uses Destroy Undead, "Holy fire burns away the mass, leaving "A Few" viscera-soaked zombies still remaining." Immediately advance to Phase 3.  

Swarm. The swarm can occupy another creature’s space and vice versa, and the swarm can move through any opening large enough for a Tiny limb. The swarm can’t regain hit points or gain temporary hit points.

Unusual Nature. The swarm doesn’t require air, food, drink, or sleep.

Phase 1: The Swarm

Armor Class 14 (natural armor)
Size Gargantuan 
Speed 40 ft. Climb 30 ft. 

Multiattack. The Swarm makes two Undead Blows attacks and one Engulfing Limbs attack.

Undead Blows. Melee Weapon Attack: +10 to hit, reach 10 ft., one target in the swarm’s reach. Hit: 28 (4d10 + 6) bludgeoning damage.

Engulfing Limbs. Melee Weapon Attack: +10 to hit, reach 0 ft., one creature in the swarm’s space. Hit: 22 (3d10+6) necrotic damage, and the creature must succeed on a DC 17 Strength or Dexterity saving throw or be partially  restrained (only able to take 1 Attack Action, Action, or bonus Action a turn). The creature can repeat the saving throw at the end of each of its turns, taking 22 (3d10+6) necrotic damage on a failed save. The creature is freed if it succeeds on this saving throw, the swarm moves out of the creature’s space, or the swarm dies.

Phase 2: The Mob

Armor Class 13 (natural armor)
Size Large 
Speed 40 ft. Climb 30 ft.
Resistance Looses resistances. Retains Poison and Necrotic Immunity.

Aura of Disgust. Upon entering Phase 2 an aura exudes from the remaining Zombies, with the viscera of the fallen clinging to their bodies. Any creature that can smell that starts its turn within 15 feet of the Mob must succeed on a DC 16 Constitution saving throw or be poisoneduntil the start of the creature’s next turn and take 6 (3d4) poison damage. On a successful saving throw, the creature is immune to the stench of all Zombie Hordes for 1 hour.

Multiattack. The Mob makes two Undead Blows attacks.

Undead Blows. Melee Weapon Attack: +8 to hit, reach 5 ft., one target in the swarm’s reach. Hit: 16 (3d8 + 4) bludgeoning damage.

Phase 3: The Few

Armor Class 12 (natural armor)
Size Medium 
Speed 30 ft. 

Aura of Disgust. Upon entering Phase 3 an aura increases in intensity from the remaining few Zombies, with the viscera of the fallen clinging to their bodies. Any creature that can smell that starts its turn within 10 feet of the few must succeed on a DC 16 Constitution saving throw or be poisoneduntil the start of the creature’s next turn and take 8 (4d4) poison damage. On a successful saving throw, the creature is immune to the stench of all Zombie Hordes for 1 hour.

Desperate Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one target in reach. Hit: 13 (2d10 + 3) piercing damage.

Relentless Remnant. At 0 HP, the creature makes one final attack on the nearest target, unless the last strike was a critical hit or radiant damage.